He then served as a tutor of the Colonna family in Rome for ~ 5 years.

Following this he moved to Florence, in 1654, to act as personal physician to the Grand dukes Ferdinand II & Cosimo III.

He was one of the first members of the Arcadia.

In 1666 he taught in the Studio at Florence, as lettore publico di lingua toscana.

His experiments, published in 1668 as Esperienze Intorno alla Generazione degl'Insetti (Experiments on the Generation of Insects) were some of the first evidence refuting "spontaneous generation" (Aristotelian abiogenesis).

Prior to these experiments it was thought that maggots formed naturally from rotting meat.

Redi, in 1676, wrote about important documents in his possession which pertained to the origins of eye glass invention and use.